Error while installing UMBRELLO in ubuntu 12.0
 

foolowing error i get

"Error in network connection"
Failed to fetch http://archive.ubuntu.com/ubuntu/poo....04.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...ntu0.1_all.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu0.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu0.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...ntu0.1_all.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...ntu0.1_all.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu0.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu0.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...ntu0.1_all.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu0.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu0.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu0.1_i386.deb 404 Not Found [IP: 91.189.92.156 80]
"

I believe you are trying to install an application, presumably using apt-get. Apt-get uses file /etc/apt/sources.list to access software repositories. Error 404 means the repository URLs, as specified in your file, are not found. You need to identify correct locations that are used for your distribution and adjust the 'sources' file accordingly.